[1] Hosp Torrecardenas, Vasc Surg Dept, Almeria, Spain
[2] Inst Invest Sanitaria Principado Asturias, Oviedo, Spain
[3] ISCIII, CIBERONC, Oviedo, Spain
[4] Univ Oviedo, Inst Univ Oncol Principado Asturias, Oviedo, Spain
[5] Univ Med Ctr Utrecht, UMC Utrecht Canc Ctr, Dept Head & Neck Surg Oncol, Utrecht, Netherlands
[6] Univ Edinburgh, Dept Surg, Edinburgh, Midlothian, Scotland
[7] Univ Edinburgh, Dept Otolaryngol Head & Neck Surg, Edinburgh, Midlothian, Scotland
[8] Univ Helsinki, Dept Otorhinolaryngol Head & Neck Surg, Helsinki, Finland
[9] Helsinki Univ Hosp, Helsinki, Finland
[10] Univ Helsinki, Fac Med, Res Programme Syst Oncol, Helsinki, Finland
[11] Karolinska Inst, Dept Clin Sci, Div Ear Nose & Throat Dis, Stockholm, Sweden
[12] Karolinska Hosp, Stockholm, Sweden
[13] Univ Udine, Sch Med, Udine, Italy
[14] Univ Edinburgh, Dept Clin Neurosci, Edinburgh, Midlothian, Scotland
[15] Int Head & Neck Sci Grp, Padua, Italy